A building company has gone into bat for the world champion Black Sox in a potential five-year deal Softball New Zealand are trumpeting as one of the most significant in the sport's history.

Golden Homes, a nationwide company involved in the Christchurch rebuild, has secured naming rights to the Black Sox and will also be supporting grassroots softball.

The sponsorship partnership was launched yesterday in Christchurch where senior company officials attempted to hit the pitching of Junior Black Sox hurler Ethan Johnston and then watched Black Sox hitters Stephen Ratu, Tyron Bartorillo and Josh Thompson swing the bat.

Softball New Zealand general manager Tony Giles declined to say how much the deal was worth but said it was "right up there, for a sport of our size".

The Press understands it is a significant six-figure-plus annual sum.

Giles said half the funding would go to the Black Sox campaign "and the other half will go to Softball New Zealand to run grassroots initiatives and programmes that will help the development of the game".

The Black Sox - who will tour Canada next month - receive $250,000 a year from High Performance Sport New Zealand, but this is their first significant commercial sponsorship for many years.

Giles said HPSNZ support was ongoing but "it doesn't fund the total campaign" with the Black Sox now competing at world championships every two years.

"This support from Golden Homes means we can fill that void in the current funding model, tour more internationally to get more exposure for us, as a brand, and have more internal domestic tours and [training] camps to allow us to prepare more for next year's [world title] defence."

Giles said the Black Sox, who have won a record six world championship gold medals, were generating more interest from the commercial sponsorship sector after their title success in Auckland last year, the test series against Australia last March and their victory at the Halberg Awards where they were won the best sporting moment category after a public vote.